Testing Arista EDU Ultra 400 (aka. Fomapan 400) with D23

[dcy]

This is Part III of my film testing saga. I feel like I'm getting better at this. I didn't make any of the mistakes I made in Parts I and II.

Recap: A while ago I took 5 rolls of film and shot a few scenes over and over so I could cut the rolls into pieces and run tests. This is the third roll.

This time we have Arista EDU Ultra 400 (aka. Fomapan 400) shot in a sunny day at EI 250 and EI 200 on my Pentax 17 half-frame camera. I cut the roll into 4 pieces and developed 3 of them in D23 stock solution at around 20°C. Inspired by a thread from @F4U , I've decided to tray straight D23 this time. The Massive Dev Chart suggests a development time of 7.5 minutes, so I decided to "bracket" that value:

1) One piece was developed for 6 min.
2) One piece was developed for 7.5 min.
3) One piece was developed for 9 min.

If the MDC is correct, the middle piece should be properly developed. From my novice point of view, they all look good to me. I like the extra shadow detail (in the trees) with EI 200. I feel that all development times show the same amount of detail in the highlights (the roof of the basilica). I would be interested to know your opinions. Without further ado, here are the results:

Start with a high-level shot of all the negatives:

Now the scans of two sample scenes:

1) D23 for 6min --- EI 250 (left) + EI 200 (right)

2) D23 for 7.5min --- EI 250 (left) + EI 200 (right)

3) D23 for 9min --- EI 250 (left) + EI 200 (right)

 

[FotoD]

Looking at the shadows, I'd rather use the El 200 negs. For contrasty scenes El 100 can sometimes be nice.

And I would probably develop for at least 7:30 min. But that depends on what the negs would be used for. (For alt processes 15 min would be better. 18x24 mm contact prints! )

 

[Milpool]

I like the EI 200 6min but 7.5 is fine too.

 

[ags2mikon]

I think you are doing very well. I would go for the EI 200 at 6-7.5 min. You will find that D-23 1:1 does not build contrast as fast as other developers when you extend development times. Here in the desert southwest that is a nice benefit. I know it is expensive, but D-23 1:1 plays very nice with TMY-2.

 

[Craig]

I'm seeing a lot of variability on your exposures within the same negative strip, so it's much harder to judge development until each frame is exposed identically.

In the first photo of all the negatives, notice how the bottom strip has the left images quite dense and the right images fairly light?

I'd want to work on metering technique to get the resulting densities on the negative consistent frame to frame. Once you have achieved that, then look at adjusting development to bring the density/contrast to where you want it.

 

[F4U]

Thank you dcy. Although i will be using a tank at 75F, I guess I have no choice but to go for 7 minutes and call it good

 

[npl]

EI 200 6-7.5min, I'd say it's pretty consistent with foma's curve (see attached)

Datasheets, first place to look.

 

[dcy]

EI 200 6-7.5min, I'd say it's pretty consistent with foma's curve (see attached)

Datasheets, first place to look.

It was. The datasheet is precisely where I got the idea of trying EI 200 and 250. However, notice that the plot you shared is for D76, not D23. The datasheet does not include times for D23. In fairness, the advice I've received in this forum for D23 is to either copy D76 times or add 10-15%. Looking back at the plot for D76, EI of 200 - 250 corresponds to 6.5-9.5 min in D76. If we add 0-15% to that we'd get 6.5-10.5 min for D23. So overall I'm happy that I covered the wider 6-9min range.


But... following this train of thought... My understanding is that the target contrast in the ISO standard is gamma = 0.6. Looking back at the D76 plot, we see that we reach gamma = 0.6 just after 6 minutes. This corresponds to an ISO of around 190.

In your opinion, would you interpret this plot to mean that, if Foma had actually followed the ISO standard and reported a film ISO based on D76 at 20°C, the would have found a true film ISO of around 200?

 

[dcy]

In the first photo of all the negatives, notice how the bottom strip has the left images quite dense and the right images fairly light?

I hope I'm not being too thick-headed, but I'm not seeing it. I actually think that the left images are light and the right ones are dense, which is what you'd expect from the fact that the left images were shot at EI 250 and the right ones at EI 200.

Here's a zoom-in to the bottom strip:

Am I just going blind? I swear I think the ones on the right are denser... "denser" means "darker", right?... more silver.

I'd want to work on metering technique to get the resulting densities on the negative consistent frame to frame. Once you have achieved that, then look at adjusting development to bring the density/contrast to where you want it.

Well, these are not consistent because I as intentionally exposing them differently in order to test which EI looks best. My metering technique is to point the camera and pray that the internal light meter does the right thing .

So far my observation is that more light = good, which I'm sure will surprise exactly no-one. But even beyond the test strips I have posted, I also shoot color and I took some shots inside the basilica with Kodak UltraMax. After getting the film back from the lab, I found that the indoor photos looked a lot better at EI 320 than EI 400, while the outdoor photos did not look any worse at EI 320.